All your calculations weren't required cause this is what he said
"We put satellites into Geosynchronous orbit which is 36000 km away"
He was talking about the altitude from mean sea level and not from the center of the Earth. And in Aerospace, we do not talk about geosynchronous orbit at 42k kms from earth's center but at 36k km from the sea level, because when we talk in terms of thrust required, we do not calculate the first 6.4 k kms ie the radius of the earth, because that would require a lot more thrust to escape the gravity, whereas in reality we don't require that much thrust. We just need o calculate the thrust required to push the satellite from 6.4k kms to 42k kms from the earth's center.
If we take your calculations, the satellite would keep moving away from earth at a very rapid pace and in a few hours escape the gravity and in no time will be lost in space.
If you're still in doubt I can do the calculations for you.